textproduct: Albany

WHAT HAS CHANGED

The expected arrival timing of showers on Thursday is now earlier in the day. As a result, thunder was mostly removed due to little to no instability present. Should this trend continue, high temperatures for tomorrow will likely need to be lowered in future forecast updates.

KEY MESSAGES

1) A weak surface low will bring rain showers to the region on Thursday with no significant impacts expected.

2) Dry and cool weather returns Friday into Saturday, before confidence increases on a low pressure system bringing a widespread rainfall on Sunday.

DISCUSSION

KEY MESSAGE 1... Mainly dry conditions will continue through tonight. Enough breaks in the clouds could allow for some patchy fog to form tonight. Otherwise, it will not be as cool as previous nights with lows in the mid-50s to lower 60s.

A weak area of low pressure will track across the area tomorrow with enough moisture to bring rain showers to much of the area. The latest CAMs show an earlier arrival time of showers compared to previous forecasts with precipitation starting in the morning for areas mainly west of the Hudson Valley and in the afternoon from the Hudson and points east. With the earlier arrival time of clouds and showers, there will likely be little to no instability present, so thunder was mostly removed from the forecast. While precipitable water values will be high on the order of 1.50 to 2.00 inches (+2 to +3 STDEV), the overall limited coverage of heavier, convective showers will likely prevent much if any hydrological concerns, though some ponding of water in urban and poor drainage areas is possible where any repeated downpours occur. Total QPF amounts look to generally range between 0.10 and 0.50 inches for most areas. Should the earlier arrival time trend continues, forecast high temperatures will likely need to be lowered several degrees due to wet-bulb effects.

KEY MESSAGE 2... A strong cold front crosses the region Thursday night into early Friday as high pressure builds back into the region from Canada. This will bring a cooler, drier and less humid air mass into the region for Friday and Saturday. A chilly night Friday night could lead to some patchy frost in parts of the Adirondacks.

Saturday will likely be the nicer of the two days this weekend as confidence continues to increase on a low pressure system tracking from the Upper Midwest eastward across the area on Sunday. Most of the global models, including the EC-AIFS and AIGFS, are in general agreement with the timing and track of this system. The region will be located within the right entrance region of an upper level jet which will allow for plenty of upper level forcing and ascent for a widespread rainfall event. Latest NBM probabilities for greater than 1 inch of rain Sunday into Monday are between 40 and 60 percent. While most of this rain should be beneficial, will monitor trends for any possible localized hydrological issues, especially ponding of water in urban and poor drainage areas. If this rain materializes, it could be a rather cool day with some areas potentially not getting out of the 50s.

As this system departs, a frontal boundary will likely stall near or south of our area to start next week. Most global models keep it south enough for high pressure to nose into the area bringing drier weather to start the week. However, the chance for some additional showers will not be too far away if this boundary ends up a little farther north. Will keep low chances for showers in for early next week due to uncertainty. Temperatures early next week will also likely remain slightly below normal, mainly in the 60s.

AVIATION /00Z THURSDAY THROUGH MONDAY/

Through 00z/Friday...A cold front will become stationary over NY and New England tonight. VFR conditions open the TAF cycle for KGFL/KALB/KPOU/KPSF with cigs 3.5-5 kft AGL especially from KALB-KPSF north to KGFL. The low-level moisture continues to increase and the development of MVFR/IFR stratus is likely overnight especially between 06Z-12Z. Some clearing of the clouds may allow for some IFR/LIFR radiative mist/fog to form especially at KGFL/KPSF. We leaned more towards lower stratus and brought MVFR conditions into KALB/KPSF/KGFL with cigs 1.5-3.0 kft AGL and then used a TEMPO for KPOU between 04Z-08Z/Thu for MVFR cigs around 2.5-3.0 kft AGL. Vsbys may also lower to MVFR levels between 06Z-12Z/Thu, and for KGFL/KPSF we lowered to IFR levels 09Z-12Z/Thu.

Some slight improvement to higher MVFR/VFR levels may occur with vsbys after 12Z/Thu, and cigs may increase back to MVFR/low VFR levels, but then a wave will move along the front bringing periods of showers especially in the late morning into the early pm, and then continue until the end of the TAF cycle. Used PROB30/TEMPO groups to bring in the showers 14Z-18Z/Thu, except for KPOU where it will be after 18Z/Thu. Expect widespread IFR/MVFR conditions in the late morning into the afternoon. The winds will become light and variable to calm tonight. The winds will vary from the east/southeast to south at less than 7 KT in the late morning through the afternoon.

Outlook...

Thursday Night: Moderate Operational Impact. Chance of SHRA. Friday: No Operational Impact. NO SIG WX. Friday Night: No Operational Impact. NO SIG WX. Saturday: No Operational Impact. NO SIG WX. Saturday Night: Moderate Operational Impact. Likely SHRA. Sunday: High Operational Impact. Definite SHRA. Sunday Night: Moderate Operational Impact. Chance of SHRA. Monday: Moderate Operational Impact. Chance of SHRA.

ALY WATCHES/WARNINGS/ADVISORIES

CT...None. NY...None. MA...None. VT...None.